﻿30 
  " 
  NEW 
  YORK 
  STATE 
  MUSEUM 
  

  

  Other 
  facts 
  may 
  be 
  studied 
  to 
  best 
  advantage 
  by 
  comparing 
  the 
  type 
  

   section 
  here 
  with 
  those 
  of 
  the 
  Little 
  Falls 
  and 
  Trenton 
  Falls 
  dis- 
  

   tricts. 
  The 
  two 
  last 
  named 
  sections 
  may 
  be 
  found 
  on 
  page 
  38 
  of 
  

   the 
  Remsen 
  quadrangle 
  bulletin.^ 
  It 
  is 
  evident, 
  therefore, 
  that 
  the 
  

   upper 
  Trenton 
  sea 
  in 
  the 
  Port 
  Leyden 
  district 
  was 
  much 
  clearer 
  

   water 
  than 
  the 
  same 
  sea 
  in 
  the 
  Little 
  Falls 
  region. 
  Also 
  the 
  

   change 
  from 
  the 
  upper 
  Trenton 
  to 
  the 
  Utica 
  was 
  much 
  more 
  

   gradual 
  at 
  Little 
  Falls 
  as 
  shown 
  by 
  the 
  deposition 
  there 
  of 
  the 
  

   Dolgeville 
  shales 
  as 
  a 
  transition 
  series. 
  In 
  passing 
  northward 
  from 
  

   Sugar 
  river 
  to 
  Martinsburg 
  the 
  pure, 
  heavy 
  bedded, 
  crystalline 
  lime- 
  

   stones 
  assume 
  even 
  greater 
  importance. 
  

  

  The 
  lowermost 
  20 
  feet 
  of 
  the 
  Trenton 
  are 
  highly 
  fossiliferous, 
  

   thin 
  bedded, 
  alternating 
  shales 
  and 
  limestones. 
  These 
  beds 
  are 
  in 
  

   sharp 
  contact 
  with 
  the 
  underlying 
  massive 
  Black 
  River 
  limestone 
  as 
  

   may 
  be 
  seen 
  along 
  Sugar 
  river; 
  along 
  Black 
  river 
  i 
  mile 
  above 
  the 
  

   mouth 
  of 
  Sugar 
  river; 
  along 
  Mill, 
  Douglass, 
  and 
  House 
  creeks 
  and 
  

   Roaring 
  brook. 
  

  

  Except 
  for 
  the 
  shale 
  area 
  at 
  Locust 
  Grove, 
  the 
  Trenton 
  lime- 
  

   stone 
  extends 
  from 
  south 
  to 
  north 
  across 
  the 
  map 
  as 
  an 
  unbroken 
  

   belt 
  whose 
  width 
  is 
  from 
  2 
  to 
  3 
  miles. 
  It 
  forms 
  the 
  summit 
  of 
  the 
  

   lower 
  great 
  terrace 
  so 
  plainly 
  shown 
  on 
  the 
  topographic 
  map. 
  

   Minor 
  terraces 
  are 
  developed 
  along 
  the 
  lines 
  of 
  outcrop 
  of 
  certain 
  

   harder 
  and 
  more 
  resistant 
  strata 
  within 
  the 
  formation. 
  The 
  vil- 
  

   lages 
  of 
  Talcottville, 
  Collinsville, 
  Turin, 
  Houseville 
  and 
  Martins- 
  

   burg 
  all 
  rest 
  upon 
  the 
  Trenton. 
  The 
  larger 
  streams 
  have 
  cut 
  

   picturesque 
  gorges 
  through 
  this 
  limestone 
  as 
  for 
  example 
  on 
  Sugar 
  

   river, 
  Mill 
  creek, 
  House 
  creek 
  and 
  Roaring 
  brook. 
  The 
  last 
  named 
  

   gorge 
  is 
  locally 
  called 
  " 
  Whitaker's 
  gulf." 
  

  

  Throughout 
  all 
  of 
  Trenton 
  time 
  the 
  ocean 
  was 
  fairly 
  teeming 
  with 
  

   animal 
  forms, 
  especially 
  brachiopods, 
  trilobites, 
  cephalopods, 
  corals 
  

   and 
  crinoids. 
  Many 
  of 
  the 
  limestone 
  beds 
  are 
  practically 
  made 
  up 
  

   of 
  fossil 
  shells. 
  The 
  writer 
  has 
  made 
  no 
  detailed 
  study 
  of 
  the 
  fos- 
  

   sils, 
  but 
  the 
  forms 
  are 
  mostly 
  the 
  same 
  as 
  those 
  decribed 
  by 
  Prosser 
  

   and 
  Cumings 
  from 
  the 
  type 
  locality 
  at 
  Trenton 
  Falls. 
  Hall 
  has 
  

   described 
  and 
  figured 
  many 
  of 
  the 
  forms 
  from 
  this 
  limestone 
  along 
  

   the 
  Black 
  river 
  valley. 
  In 
  the 
  lowest 
  Trenton 
  beds 
  the 
  writer 
  has 
  

   seen 
  specimens 
  of 
  orthoceras 
  several 
  feet 
  long 
  and 
  5 
  or 
  6 
  inches 
  in 
  

   diameter. 
  

  

  ' 
  N. 
  Y. 
  State 
  Mus. 
  Bui. 
  126. 
  p. 
  38. 
  

  

  